Micro controller based fiber optic light sensor for smart space

The need of sensors has grown rapidly in recent years for industrial control, automation & consumer applications. Apart from its conventional use in communication, Optical fibers find wide applications in of photoelectric sensors. Smart Spaces require large amounts of sensor data to be transported to networked processing resources. In view of the wider scope and increasing importance of the fiber optic sensor technology, and microcontrollers the paper reports the development of intensity modulated sensors using plastic fiber light to be used in smart spaces. In case of simple fiber optic sensor the measurand such as displacement, force, pressure, temperature modulates the intensity of light propagating through the optical fiber and the modulating zone. The modulated light changes the detector output, which can be further processed and calibrated to give the value of the measurand. In the present study the ambient light is sensed using optical fiber and the light intensity of the led bulb is controlled using PWM, so that the average light in the room remains same throughout the day.